Manatees Revisited

Six years after starting his research into the ways of the shy, elusive manatee, professor of biology Chuck Grossman is diving into waves of new discoveries. This year, he and his students are analyzing the animals’ high-frequency squeaks and squawks with 24-hour-a-day recordings. The sounds travel live through a transponder in their tank at the Cincinnati Zoo to computers in the biology lab via Internet cables.

“We have more than 3,000 recorded squeaks, and it’s very clear the animals are generating all different kinds of sounds,” says Grossman, director of the Midwest Manatee Research Project. “But we don’t know what they’re saying. It’s like a code we’re trying to break. We know the females talk to their babies, and the babies talk back. But we want to learn when they make sounds, what time do they make them, what is their Circadian rhythm.”

Researchers still aren’t sure how the manatees make their sounds. Moving air is certainly part of it, but the structures involved are still under investigation, Grossman says. But that is work for another day. The final goal is to protect the animals from dangerous speed boats, which they don’t seem to hear.